A180746 Partial sums of A004144.

1, 3, 6, 10, 16, 23, 31, 40, 51, 63, 77, 93, 111, 130, 151, 173, 196, 220, 247, 275, 306, 338, 371, 407, 445, 487, 530, 574, 620, 667, 715, 764, 818, 874, 931, 990, 1052, 1115, 1179, 1245, 1312, 1381, 1452, 1524, 1600, 1677, 1756, 1837, 1920, 2004, 2090, 2178

Offset

1,2

Links

Table of n, a(n) for n=1..52.

Formula

a(n) = Sum_{i=1..n} A004144(i).

Mathematica

fQ[n_] := If[n > 1, First@ Union@ Mod[ First@# & /@ FactorInteger@ n, 4] != 1, True]; Accumulate@ Select[ Range@ 90, fQ]

Crossrefs

Cf. A004144.

Sequence in context: A330133 A025701 A025744 * A025714 A025729 A011913

Adjacent sequences: A180743 A180744 A180745 * A180747 A180748 A180749

Keyword

nonn

Author

Jonathan Vos Post, Sep 19 2010

Extensions

a(21) and a(50) corrected by Georg Fischer, Aug 29 2020

Status

approved